Halperin told The Sun newspaper in Britain how he interviewed two of Jackson's alleged male lovers, with one claiming the pop star would sneak out of his home dressed as a woman for late night rendezvous.

One told Halperin: "The very first time he had sex with me he said, 'The King of Pop's going to lick your lollipop'. I still laugh thinking about that."

Halperin says he interviewed many people for his book, Unmasked: The Final Years of Michael Jackson, and was repeatedly told the pop star was gay.

"Virtually everybody has told me," the author told the newspaper.

"Even those who are his most ardent defenders, people who maintain he is innocent of the molestation charges, insist that he is homosexually inclined."

One unnamed source is quoted in Halperin's book as saying Jackson's lovers included a waiter, aspiring actor and construction worker.

"Michael would leave the house in disguise, often dressed as a woman, and would go to meet his boyfriend at a motel that was one of (Las) Vegas's grungiest dives," the source said.

"Michael was broke. He struggled to put food on the table for his children. It was all he could afford then."

Jackson had repeatedly denied being gay before his sudden death in late June.

A former bodyguard who worked with the singer has also claimed that Jackson had a secret girlfriend shortly before his death.

Meanwhile, Jackson's father Joe wants the singer's three children to go on a world tour in 2010.

The Sun said Joe Jackson, who managed a young Michael and his four brothers in the Jackson Five, had approached Prince Michael, 12, Paris, 11, and seven-year-old Prince Michael II.